##// END OF EJS Templates
tracked-key: remove the dual write and rename to tracked-hint...
tracked-key: remove the dual write and rename to tracked-hint The dual-write approach was mostly useless. As explained in the previous version of the help, the key had to be read twice before we could cache a value. However this "read twice" limitation actually also apply to any usage of the key. If some operation wants to rely of the "same value == same tracked set" property it would need to read the value before, and after running that operation (or at least, after, in all cases). So it cannot be sure the operation it did is "valid" until checking the key after the operation. As a resultat such operation can only be read-only or rollbackable. This reduce the utility of the "same value == same tracked set" a lot. So it seems simpler to drop the double write and to update the documentation to highlight that this file does not garantee race-free operation. As a result the "key" is demoted to a "hint". Documentation is updated accordingly. Differential Revision: https://phab.mercurial-scm.org/D12201

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shallowrepo.py
351 lines | 11.8 KiB | text/x-python | PythonLexer
# shallowrepo.py - shallow repository that uses remote filelogs
#
# Copyright 2013 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import os
from mercurial.i18n import _
from mercurial.node import hex, nullrev
from mercurial import (
encoding,
error,
localrepo,
match,
pycompat,
scmutil,
sparse,
util,
)
from mercurial.utils import procutil
from . import (
connectionpool,
constants,
contentstore,
datapack,
fileserverclient,
historypack,
metadatastore,
remotefilectx,
remotefilelog,
shallowutil,
)
# These make*stores functions are global so that other extensions can replace
# them.
def makelocalstores(repo):
"""In-repo stores, like .hg/store/data; can not be discarded."""
localpath = os.path.join(repo.svfs.vfs.base, b'data')
if not os.path.exists(localpath):
os.makedirs(localpath)
# Instantiate local data stores
localcontent = contentstore.remotefilelogcontentstore(
repo, localpath, repo.name, shared=False
)
localmetadata = metadatastore.remotefilelogmetadatastore(
repo, localpath, repo.name, shared=False
)
return localcontent, localmetadata
def makecachestores(repo):
"""Typically machine-wide, cache of remote data; can be discarded."""
# Instantiate shared cache stores
cachepath = shallowutil.getcachepath(repo.ui)
cachecontent = contentstore.remotefilelogcontentstore(
repo, cachepath, repo.name, shared=True
)
cachemetadata = metadatastore.remotefilelogmetadatastore(
repo, cachepath, repo.name, shared=True
)
repo.sharedstore = cachecontent
repo.shareddatastores.append(cachecontent)
repo.sharedhistorystores.append(cachemetadata)
return cachecontent, cachemetadata
def makeremotestores(repo, cachecontent, cachemetadata):
"""These stores fetch data from a remote server."""
# Instantiate remote stores
repo.fileservice = fileserverclient.fileserverclient(repo)
remotecontent = contentstore.remotecontentstore(
repo.ui, repo.fileservice, cachecontent
)
remotemetadata = metadatastore.remotemetadatastore(
repo.ui, repo.fileservice, cachemetadata
)
return remotecontent, remotemetadata
def makepackstores(repo):
"""Packs are more efficient (to read from) cache stores."""
# Instantiate pack stores
packpath = shallowutil.getcachepackpath(repo, constants.FILEPACK_CATEGORY)
packcontentstore = datapack.datapackstore(repo.ui, packpath)
packmetadatastore = historypack.historypackstore(repo.ui, packpath)
repo.shareddatastores.append(packcontentstore)
repo.sharedhistorystores.append(packmetadatastore)
shallowutil.reportpackmetrics(
repo.ui, b'filestore', packcontentstore, packmetadatastore
)
return packcontentstore, packmetadatastore
def makeunionstores(repo):
"""Union stores iterate the other stores and return the first result."""
repo.shareddatastores = []
repo.sharedhistorystores = []
packcontentstore, packmetadatastore = makepackstores(repo)
cachecontent, cachemetadata = makecachestores(repo)
localcontent, localmetadata = makelocalstores(repo)
remotecontent, remotemetadata = makeremotestores(
repo, cachecontent, cachemetadata
)
# Instantiate union stores
repo.contentstore = contentstore.unioncontentstore(
packcontentstore,
cachecontent,
localcontent,
remotecontent,
writestore=localcontent,
)
repo.metadatastore = metadatastore.unionmetadatastore(
packmetadatastore,
cachemetadata,
localmetadata,
remotemetadata,
writestore=localmetadata,
)
fileservicedatawrite = cachecontent
fileservicehistorywrite = cachemetadata
repo.fileservice.setstore(
repo.contentstore,
repo.metadatastore,
fileservicedatawrite,
fileservicehistorywrite,
)
shallowutil.reportpackmetrics(
repo.ui, b'filestore', packcontentstore, packmetadatastore
)
def wraprepo(repo):
class shallowrepository(repo.__class__):
@util.propertycache
def name(self):
return self.ui.config(b'remotefilelog', b'reponame')
@util.propertycache
def fallbackpath(self):
path = repo.ui.config(
b"remotefilelog",
b"fallbackpath",
repo.ui.config(b'paths', b'default'),
)
if not path:
raise error.Abort(
b"no remotefilelog server "
b"configured - is your .hg/hgrc trusted?"
)
return path
def maybesparsematch(self, *revs, **kwargs):
"""
A wrapper that allows the remotefilelog to invoke sparsematch() if
this is a sparse repository, or returns None if this is not a
sparse repository.
"""
if revs:
ret = sparse.matcher(repo, revs=revs)
else:
ret = sparse.matcher(repo)
if ret.always():
return None
return ret
def file(self, f):
if f[0] == b'/':
f = f[1:]
if self.shallowmatch(f):
return remotefilelog.remotefilelog(self.svfs, f, self)
else:
return super(shallowrepository, self).file(f)
def filectx(self, path, *args, **kwargs):
if self.shallowmatch(path):
return remotefilectx.remotefilectx(self, path, *args, **kwargs)
else:
return super(shallowrepository, self).filectx(
path, *args, **kwargs
)
@localrepo.unfilteredmethod
def commitctx(self, ctx, error=False, origctx=None):
"""Add a new revision to current repository.
Revision information is passed via the context argument.
"""
# some contexts already have manifest nodes, they don't need any
# prefetching (for example if we're just editing a commit message
# we can reuse manifest
if not ctx.manifestnode():
# prefetch files that will likely be compared
m1 = ctx.p1().manifest()
files = []
for f in ctx.modified() + ctx.added():
fparent1 = m1.get(f, self.nullid)
if fparent1 != self.nullid:
files.append((f, hex(fparent1)))
self.fileservice.prefetch(files)
return super(shallowrepository, self).commitctx(
ctx, error=error, origctx=origctx
)
def backgroundprefetch(
self, revs, base=None, repack=False, pats=None, opts=None
):
"""Runs prefetch in background with optional repack"""
cmd = [procutil.hgexecutable(), b'-R', repo.origroot, b'prefetch']
if repack:
cmd.append(b'--repack')
if revs:
cmd += [b'-r', revs]
# We know this command will find a binary, so don't block
# on it starting.
kwargs = {}
if repo.ui.configbool(b'devel', b'remotefilelog.bg-wait'):
kwargs['record_wait'] = repo.ui.atexit
procutil.runbgcommand(
cmd, encoding.environ, ensurestart=False, **kwargs
)
def prefetch(self, revs, base=None, pats=None, opts=None):
"""Prefetches all the necessary file revisions for the given revs
Optionally runs repack in background
"""
with repo._lock(
repo.svfs,
b'prefetchlock',
True,
None,
None,
_(b'prefetching in %s') % repo.origroot,
):
self._prefetch(revs, base, pats, opts)
def _prefetch(self, revs, base=None, pats=None, opts=None):
fallbackpath = self.fallbackpath
if fallbackpath:
# If we know a rev is on the server, we should fetch the server
# version of those files, since our local file versions might
# become obsolete if the local commits are stripped.
localrevs = repo.revs(b'outgoing(%s)', fallbackpath)
if base is not None and base != nullrev:
serverbase = list(
repo.revs(
b'first(reverse(::%s) - %ld)', base, localrevs
)
)
if serverbase:
base = serverbase[0]
else:
localrevs = repo
mfl = repo.manifestlog
mfrevlog = mfl.getstorage(b'')
if base is not None:
mfdict = mfl[repo[base].manifestnode()].read()
skip = set(pycompat.iteritems(mfdict))
else:
skip = set()
# Copy the skip set to start large and avoid constant resizing,
# and since it's likely to be very similar to the prefetch set.
files = skip.copy()
serverfiles = skip.copy()
visited = set()
visited.add(nullrev)
revcount = len(revs)
progress = self.ui.makeprogress(_(b'prefetching'), total=revcount)
progress.update(0)
for rev in sorted(revs):
ctx = repo[rev]
if pats:
m = scmutil.match(ctx, pats, opts)
sparsematch = repo.maybesparsematch(rev)
mfnode = ctx.manifestnode()
mfrev = mfrevlog.rev(mfnode)
# Decompressing manifests is expensive.
# When possible, only read the deltas.
p1, p2 = mfrevlog.parentrevs(mfrev)
if p1 in visited and p2 in visited:
mfdict = mfl[mfnode].readfast()
else:
mfdict = mfl[mfnode].read()
diff = pycompat.iteritems(mfdict)
if pats:
diff = (pf for pf in diff if m(pf[0]))
if sparsematch:
diff = (pf for pf in diff if sparsematch(pf[0]))
if rev not in localrevs:
serverfiles.update(diff)
else:
files.update(diff)
visited.add(mfrev)
progress.increment()
files.difference_update(skip)
serverfiles.difference_update(skip)
progress.complete()
# Fetch files known to be on the server
if serverfiles:
results = [(path, hex(fnode)) for (path, fnode) in serverfiles]
repo.fileservice.prefetch(results, force=True)
# Fetch files that may or may not be on the server
if files:
results = [(path, hex(fnode)) for (path, fnode) in files]
repo.fileservice.prefetch(results)
def close(self):
super(shallowrepository, self).close()
self.connectionpool.close()
repo.__class__ = shallowrepository
repo.shallowmatch = match.always()
makeunionstores(repo)
repo.includepattern = repo.ui.configlist(
b"remotefilelog", b"includepattern", None
)
repo.excludepattern = repo.ui.configlist(
b"remotefilelog", b"excludepattern", None
)
if not util.safehasattr(repo, 'connectionpool'):
repo.connectionpool = connectionpool.connectionpool(repo)
if repo.includepattern or repo.excludepattern:
repo.shallowmatch = match.match(
repo.root, b'', None, repo.includepattern, repo.excludepattern
)